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PubMed1994

Frequency of achieving optimal reperfusion with thrombolysis in acute myocardial infarction (analysis of four German multicenter studies).

Patients from 4 German multicenter studies on thrombolysis in acute myocardial infarction (AMI) were retrospectively evaluated to assess the incidence of optimal reperfusion, defined as a completely perfused infarct vessel after 90 minutes, without subsequent death or reinfarction, and without reocclusion or deterioration of flow in control angiograms. Of 907 patients with a 90-minute angiogram, 75% had an open infarct vessel by conventional definition (perfusion grade 2 or 3 according to the criteria of the Thrombolysis in Myocardial Infarction [TIMI] study). However, only 62% had TIMI grade 3 complete perfusion. Of the 561 patients with such primary treatment success, 106 (19%) had secondary treatment failure by death, reinfarction, or subtotal or total reocclusion of the infarct vessel. In a subset of 668 patients with a first angiogram after 60 minutes, conventional patency was 70%, complete perfusion 51%, and an optimal perfusion result was achieved in only 42%. The efficacy of thrombolysis in AMI is substantially overestimated by conventional 90-minute patency rates.

Adult↗
PubMed2001

Multicentered study of viral acute lower respiratory infections in children from four cities of Argentina, 1993-1994.

This study describes the first multicentered study of acute lower respiratory infection viral etiology in young children from four different geographical areas of Argentina. A total of 1,278 children under 5 years of age, hospitalized in primary care centers from Buenos Aires, Córdoba, Santa Fé and Mar del Plata cities during a 2-year period were studied (1993-1994). Nasopharyngeal aspirates were investigated for respiratory syncytial virus (RSV), adenovirus, parainfluenza, and influenza A and B viruses by indirect immunofluorescence. Out of the patients studied, 946 (74%) were under 1 year of age. Viruses were detected in 399 patients (32%). RSV was observed in 25.3% of the samples, representing 78.2% of all viral positive cases. Adenoviruses were detected in 2.5% of the cases, parainfluenza in 2.2%, influenza A in 2.1%, and influenza B in 0.2%. Compared with other viruses, the higher RSV frequency was statistically significant (P < 0.000). Most RSV cases were detected between May and September with a significant peak in July (P < 0.000). Pneumonia was observed in 46% of the patients, bronchiolitis in 41% and other entities in 13%. The case fatality rate observed during the 2 year study was 0.73%. Most of the above respiratory viruses were detected in the four cities, however, the frequency of RSV and influenza were different in the southern city.

Acute Disease↗
PubMed1994

Multicenter study of childhood headache.

This multicenter study reports the results obtained between 1990 and 1991 by the Study Group for Childhood Headache of the Italian Neuropediatric Society. Standardized computerized case sheets were used in order to increase the number of young patients studied and obtain more homogeneous results. A clinical diagnosis of headache was made in 600 patients (314 female and 286 male) between 4 and 12 years of age, in accordance with the classification set down by the International Headache Society. Clinical symptoms and follow-up were more severe in children with migraine as opposed to headache. No sequence of associated neurological and neurovegetative symptoms was observed at onset of headache, and some (phono-photophobia, pallor, drowsiness, abdominal pains) were much more prevalent than others. Because of the patient's age we studied only the treatment of acute attack and did not take account of chronic treatment. In childhood the clinical course of primary headache tends to improve spontaneously, and we believe that prevention of headache attacks should be carried out only in very rare individual cases.

Acute Disease↗
PubMed1998

Risedronate in the treatment of Paget's disease of bone: an open label, multicenter study.

An open-label, multicenter study was conducted to determine the efficacy and safety of oral risedronate (a pyridinyl bisphosphonate) in 162 patients (102 men, 60 postmenopausal women; mean age, 68 years) with moderate to severe Paget's disease of bone (mean serum alkaline phosphatase [ALP] approximately seven times the upper limit of normal). Patients were treated with oral risedronate, 30 mg/day for 84 days, followed by 112 days without treatment. This 196-day cycle was repeated once if serum ALP did not normalize or increased from the nadir value by > or = 25%. At the end of the first and second cycles, the mean percentage decreases for serum ALP were 65.7% and 69.1%, and for urinary hydroxyproline/creatinine 50.4% and 66.9%, respectively. The decreases from baseline in ALP and urinary hydroxyproline/creatinine were significant (p < 0.001). Normalization of serum ALP was observed in 86 patients (53.8%): 53 during the first treatment cycle and 33 during the second. There was a significant proportion of patients reporting a decrease in the pagetic bone pain at days 84 and 196 (p < 0.001). Overall, risedronate was well tolerated. Five patients withdrew due to adverse events, none of which were considered to be drug related. In conclusion, 30 mg of oral risedronate administered daily for 84 days significantly reduced the biochemical indices of disease activity and was associated with pain reduction in patients with moderate to severe Paget's disease of bone. Normalization of ALP was observed in the majority of patients. Repeated administration of risedronate was shown to be beneficial. In general, risedronate was well tolerated and demonstrated a good safety profile.

Administration, Oral↗
PubMed1995

Implant survival rates in partially edentulous patients: a 3-year prospective multicenter study.

PURPOSE: This multicenter investigation is an interim 3-year survival report of a 5-year prospective study using Brånemark osseointegrated implants in partially edentulous patients. MATERIALS AND METHODS: Previously defined patient characteristics and clinical parameters were related to implant survival using lifetable analysis. RESULTS: Three years after prosthesis insertion, 460 implants placed in 139 patients remained in the study. Cumulative success rates for maxillary implants (92.5%) were less than for mandibular implants (94.8%), with an overall cumulative success rate of 93.9%. CONCLUSION: Failures were associated with poor bone quality, smaller implant sizes, and a higher plaque index, and were more likely to occur before loading. A 4% incidence of residual long-term inferior alveolar nerve paresthesia was higher than previously reported.

Adolescent↗
PubMed1992

[An epidemiogenetic study of typical retinitis pigmentosa in Japan--a preliminary report of nationwide, multicenter study].

We performed a nationwide, multicenter study of typical retinitis pigmentosa with reference to the inheritance patterns of the disease. A total of 253 probands were registered during two months of 1989, and an analysis of the parental consanguinity of 182 probands with the method of inbreeding coefficient enabled us to estimate the relative prevalence of genetic types; autosomal recessive trait: 47.6%; autosomal dominant trait: 17.3%; sporadic cases: 34.6%. A comparison of the results with previous studies has indicated a decrease in the prevalence of the autosomal recessive trait and an increase in the sporadic cases, as would be expected from the decrease in consanguineous marriages and offsprings in the past few decades in Japan. X-linked retinitis pigmentosa was rarely identified, but precise evaluation of its frequency needs further investigation.

Adolescent↗
PubMed1996

[Comparison of sevoflurane and isoflurane in ambulatory surgery. Results of a multicenter study].

UNLABELLED: A multicenter, randomized, comparative phase III study evaluating the effect of sevoflurane versus isoflurane in adult outpatients was performed. The aim of the study was to compare (1) maintenance of anaesthesia and (2) how rapidly and easily the patients emerge from the anaesthetic and recover. METHODS: Outpatients were included who underwent scheduled surgical procedures of an anticipated duration of up to 3 h and an anticipated length of hospitalization of less than 24 h post-anaesthesia. Five hundred patients were randomly selected to receive either sevoflurane (n = 247) or isoflurane (n = 253), each administered with oxygen (30-50%) in nitrous oxide. Efficacy was evaluated through the measurement of times of recovery parameters and tests like the objective pain-discomfort scale, the visual analogue scale, and the digit symbol substitution test. Safety was evaluated by monitoring adverse experience, clinical laboratory and non-laboratory testing and physical assessments. RESULTS: No statistical differences were observed between the two treatment groups with respect to demographics and ASA class. All study drug concentrations during each anaesthetic phase were statistically lower in the sevoflurane (average concentration 0.61 MAC) compared to the isoflurane (average concentration 0.70 MAC) group. The mean time to emergence was statistically shorter in the sevoflurane group (8.2 min) than in the isoflurane group (9.3 min). The mean time to response to commands (8.5 min vs 9.8 min) and the mean time to orientation (10.6 min vs 13.0 min) were also statistically shorter in the sevoflurane than in the isoflurane group. The EEG results showed a faster decrease in delta activity and a faster increase in alpha activity in the sevoflurane group than in the isoflurane group, indicating faster awakening. No statistical differences were observed between the two treatment groups for the mean time to any of the remaining post-anaesthesia events. Bradycardia was observed in a statistcally higher percentage of patients in the sevoflurane group (6%) than in the isoflurane group (2%). No other statistical differences were observed between the two treatment groups concerning the incidence of study drug-related adverse experience. The most common adverse experiences were nausea and vomiting. At all post-anaesthesia time points, higher serum inorganic fluoride concentrations were observed in the sevoflurane (maximum 30.2 mumol/l) than in the isoflurane group. No clinical or laboratory renal insufficiency was noted. Eighty-seven percent of patients in the sevoflurane group would request the same anaesthetic technique compared to only 79% of patients in the isoflurane group. CONCLUSIONS: Sevoflurane was as safe as isoflurane for anaesthesia in adult outpatients. Patients who received sevoflurane had statistically significantly shorter recovery parameters than isoflurane patients.

Adolescent↗
PubMed1990

Angiographic assessment of patency and reocclusion: preliminary results of the Dutch APSAC Reocclusion Multicenter Study (ARMS).

The main objective of the ARMS (APSAC Reocclusion Multicenter Study) trial was to obtain patency and reocclusion data. In an open multicenter study, a total of 156 patients were treated with 30 U of anistreplase or anisoylated plasminogen streptokinase activator complex (APSAC) within 4 h after onset of pain. Patency of the infarct-related vessel was assessed by coronary angiography performed 90 minutes after anistreplase administration. In those patients with a patent infarct-related vessel at 90 min, repeat coronary angiography was performed at 24 h to assess the reocclusion rate. Two independent cardiologists evaluated the angiograms and scored the coronary artery perfusion of the infarct-related vessel. The preliminary data of the first 148 patients indicate that the patency rate at 90 min was 73-75% and the reocclusion rate at 24 h was 4%. This patency rate corresponds with previous studies. The low reocclusion rate is noteworthy and probably reflects the prolonged action of anistreplase.

Acute Disease↗
PubMed1992

Distributed data analysis in a multicenter study: the CARDIA Study.

Unlike distributed data entry, which is used in many large epidemiologic studies and multicenter clinical trials, distributed data analysis is a relatively new concept. This paper reports on the usefulness of such a system in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. CARDIA distributes the entire examination dataset to participating centers soon after completion of each round of data collection. The process was designed to encourage more numerous, diverse, and rapid publications, and to allow for more efficient use of the manpower and expertise in centers. Responsibilities of the coordinating center have changed from a conventional coordinating center but remain substantial due to the need for collating, monitoring, verifying, and documenting the distributed data analysis (DDA) system. DDA is successful from the standpoint of implementation and operation--21 manuscripts representing work analyzed at six participating centers had been submitted for publication within 3.5 years of the completion of the baseline examination.

Adolescent↗
PubMed1991

Quality control in antimicrobial disk susceptibility testing: a Belgian multicenter study.

A Belgian multicenter trial was conducted to evaluate problems encountered with quality control results of antimicrobial disk susceptibility testing and to compare the performance of BBL disks and Rosco tablets. Over a period of four weeks 18 laboratories daily tested three reference strains against eight antibiotics. A standardised method was used by all participants. For all results together 10.4% and 7.3% of the measurements with BBL disks and Rosco tablets, respectively, were outside the recommended range. Major problems were observed for some specific strain-antibiotic combinations. Standard deviations were similar for both systems; their precision was comparable. The results suggest that cooperation between manufacturers and some reference laboratories could be improved in order to establish optimal quality control limits.

Anti-Bacterial Agents↗
PubMed1985

Conference on insulin pump therapy in diabetes. Multicenter study of effect on microvascular disease. The Central Biochemistry Laboratory in the Multicenter Kroc Study. Problems and proposals.

The advantages of a multicenter trial can easily be lost if results from individual centers cannot be safely combined for statistical analysis. One objective of the Kroc Study was to develop methods that would allow valid amalgamation of results from laboratories at the six clinical centers and a central biochemical laboratory at the University of Newcastle upon Tyne. Responsibilities of the local laboratories, in addition to measurement of plasma glucose, creatinine, and glycosylated hemoglobin, were to obtain and prepare samples for measurement of plasma glucose, glycosylated hemoglobin, and serum lipids at the central laboratory, of C-peptide at the University of Chicago, and to collect and prepare samples for measurement of urinary albumin excretion at Guy's Hospital. The central laboratory was additionally to provide a system to ensure the comparability of plasma glucose determinations between and within centers, and to advise on common procedures for sample handling. Major problems were encountered with sample labeling, dispatch, and transport to the central laboratory. Although central determinations of plasma glucose and serum lipids were still possible in transported specimens, central assay of glycosylated hemoglobin proved inaccurate and useless. Compliance with the plasma glucose quality control program was variable among centers. Although the difference between the centers recording the highest and lowest values was 24.6% of the mean estimate of plasma glucose level, correlation between local and central plasma glucose determinations was good (r = 0.99, see pages 22-26).(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Glucose↗
PubMed1997

Cisapride use during human pregnancy: a prospective, controlled multicenter study.

The objective of this prospective multicenter study was to determine whether cisapride is associated with increased risk of malformations, spontaneous abortions, or decreased birthweight when used during pregnancy. Cases were paired for age, smoking, and alcohol consumption with controls exposed to nonteratogens, as well as with disease-paired controls. One hundred and twenty-nine pregnant women were exposed to cisapride during pregnancy, including 88 during the period of fetal organogenesis. There were no differences in maternal history, birthweight, gestational age at delivery, and rates of livebirths, spontaneous or therapeutic abortions, fetal distress, and major or minor malformations among groups. It is concluded that exposure to cisapride during pregnancy is not associated with a major increased risk of malformations or spontaneous abortions or with decreased birthweight.

Abnormalities, Drug-Induced↗
PubMedDate not supplied

[The recurrence of duodenal ulcer in patients undergoing treatment with ranitidine and placebo. A multicenter study].

This randomised, double-blind multicenter study was conducted in order to evaluate the long-term effect (one year) of 150 mg ranitidine vs placebo in 51 patients with healed duodenal ulcer. Seventeen patients had ulcer recurrence at the end of follow-up, one among the 24 patients that received ranitidine and 16 among the 27 patients that received placebo (p = 0.00009). No side effects was detected. Our results support the usefulness of a one-year maintenance therapy with 150 mg ranitidine.

Adult↗
PubMed2000

Efficacy, safety and patient satisfaction outcomes of the AMS 700CX inflatable penile prosthesis: results of a long-term multicenter study. AMS 700CX Study Group.

PURPOSE: We performed a long-term multicenter study of the AMS 700CX 3-piece inflatable penile prosthesis, focusing on longevity, morbidity and patient satisfaction in men implanted up to 134 months with a median followup of 47.7 months. MATERIALS AND METHODS: We performed a large scale retrospective multicenter study in 2 phases. Phase 1 was a medical record review of 372 men who underwent implantation with the AMS 700CX penile prosthesis from 1987 to 1996 by 7 frequent penile prosthesis implanters. Phase 2 included a structured telephone interview of 207 patients by a neutral observer. RESULTS: For the 372 men in phase 1 mean device mechanical reliability plus or minus standard deviation was 92.1% + or - 3.3% after 3 and 86.2% + or - 4.6% after 5 years. Patient age was 21 to 79 years (mean 57.6 + or - 11.0) at implantation. The etiology of erectile dysfunction was vascular in 27.7% of the cases, Peyronie's disease in 16.9%, diabetes mellitus in 12.9% and radical surgery in 11.6%. Of the men 55.6% received previous treatment for erectile dysfunction. Postoperative infection and device malfunction developed in 3.2% and 17.5% of the cases, respectively. Of the 207 men interviewed in phase 2, 86% still had an AMS 700CX penile prosthesis implanted, including 87.1% with erection suitable for coitus. Currently 79% of those with a device use it at least twice monthly and 88.2% would recommend an implant to a relative or friend. CONCLUSIONS: The AMS 700CX penile implant produced suitable erection and excellent patient satisfaction at long-term followup in the majority of men. Implant reliability is excellent and postoperative morbidity is low.

Adult↗
PubMed1992

Endoscopic release of the carpal tunnel: a randomized prospective multicenter study.

A 10-center randomized prospective multicenter study of endoscopic release of the carpal tunnel was carried out. Surgery was performed with a new device for transecting the transverse carpal ligament while control hands were treated with conventional open surgery. There were 122 patients in the study; 25 had carpal tunnel surgery on both hands and 97 had surgery on one hand. Of the surgical procedures, 65 were in the control group and 82 were in the device group. The endoscopic device was coupled to a fiberoptic light and a video camera. A trigger-activated blade was used to incise the transverse carpal ligament. After surgery, the best predictors of return to work and to activities of daily living were strength and tenderness variables. For patients in the device group with one affected hand, the median time for return to work was 21 1/2 days less than that for the control group. Two patients treated with the endoscopic device required reoperation by open surgical decompression; only one of these had incomplete release with the device. Two patients in the device group experienced transient ulnar neurapraxia.

Activities of Daily Living↗
PubMed1999

Treatment of toxoplasmosis during pregnancy: a multicenter study of impact on fetal transmission and children's sequelae at age 1 year.

OBJECTIVE: Toxoplasmosis during pregnancy can cause fetal infection, with unpredictable sequelae in later life. We measured the effects of prenatal antibiotic therapy on the fetomaternal transmission of Toxoplasma gondii and on the appearance of sequelae in the congenitally infected child at age 1 year. STUDY DESIGN: In a multicenter study we investigated consecutive women with Toxoplasma seroconversion during pregnancy. Data were obtained from 144 women recruited in 5 different Toxoplasma reference centers. Through multivariate analysis we assessed the association between transmission and appearance of sequelae as a function of the following parameters: estimated gestational age at infection, administration of antibiotic therapy, duration of antibiotic therapy, and time lapse between infection and the start of antibiotic therapy. RESULTS: Sixty-four of the 144 women (44%) gave birth to a congenitally infected infant. Multivariate analysis showed that transmission was predicted neither by whether antibiotics had been administered nor by the time lapse between infection and the start of antibiotic therapy, but only by the gestational age at which maternal infection occurred (P <.0001). Sequelae were found in 19 children (13%), 9 of whom (6%) had severe sequelae. Administration of antibiotics was predictive of the absence of sequelae (P =.026, odds ratio 0.30, 95% confidence interval 0.104-0.863), in particular the absence of severe sequelae (P =.007, odds ratio 0.14, 95% confidence interval 0.036-0.584). The sooner antibiotics were given after the infection, the less frequently sequelae were seen (P =. 021). CONCLUSION: Prenatal antibiotic therapy after toxoplasmosis during pregnancy had no impact on the fetomaternal transmission rate but reduced the rate of sequelae among the infected infants. The early start of treatment resulted in a significant reduction in the number of severely affected infants.

Animals↗
PubMed1992

[Clinical and prognostic significance of echocardiographic parameters in dilated cardiomyopathy: a prospective study on 225 patients. The Italian Multicenter Study of Cardiomyopathies Group].

To assess the prognostic role of echocardiographic indexes and their relation to clinical conditions, 225 patients with dilated cardiomyopathy were studied prospectively. All cases had a normal coronary angiogram and non specific endomyocardial biopsy findings. 163 men (72.4%) and 62 women (27.6%), mean age 41.5 +/- 12.3 (range 8-61), were studied. Clinical, electrocardiographic and echocardiographic parameters, normalized for body surface area, were tested according to NYHA class and presence of segmental or diffuse wall motion abnormalities. One hundred-four patients were in NYHA class I-IIa, 94 were in class IIb-III and 27 were in class IV. Left ventricular end systolic diameter index, right ventricular end diastolic diameter index, left atrial diameter index, left ventricular fractional shortening and ejection fraction, and radius to wall thickness ratio were significantly more impaired in patients with more severe symptoms. Twenty-eight patients (13%) showed segmental wall motion abnormalities and had smaller left ventricular end systolic and left atrial diameter index and higher left ventricular fractional shortening and ejection fraction. During a mean follow up of 23 +/- 15 months (range 1-67 months), 25 patients (11.1%) died from cardiac causes and 16 (7.1%) underwent heart transplant because of refractory heart failure. Prognostic evaluation was performed separately for cardiovascular mortality alone and for cardiac events (cardiovascular mortality and heart transplantation). At Cox multivariate analysis only right ventricular end diastolic diameter index (p < 0.005) predicted cardiovascular mortality, while left atrial diameter index (p < 0.001), right ventricular end diastolic diameter index (p < 0.01) and left ventricular ejection fraction (p < 0.05) were significant independent predictors of cardiac events.

Adolescent↗